A simple vaccine can prevent a disease like polio. But can we stop something like depression before it develops? Neuroscientist Rebecca Brachman says the possibility could be closer than we think.

About Rebecca Brachman

Rebecca Brachman is a neuroscientist focusing on preventative psychopharmacology, a field that aims to develop drugs which prevent mental illness.

Brachman is also a writer who works with NeuWrite to train effective science communicators.

She was a fellow at the National Institutes of Health and is a 2017 TED Fellow. She received her Ph.D. from Columbia University.

Copyright 2017 NPR. To see more, visit http://www.npr.org/.

GUY RAZ, HOST:

It's the TED Radio Hour from NPR. I'm Guy Raz. And on the show today, ideas about prevention. So there are some things like experiencing a stressful or traumatic event that are pretty hard to prevent. But the after effects, the depression, the PTSD could maybe one day be a thing of the past. Do you think, in theory, something like depression can be prevented before it happens?

REBECCA BRACHMAN: I think depression is a word we use to mean many different things.

RAZ: This is Rebecca Brachman. She's a neuroscientist.

BRACHMAN: But if you are referring to a certain subtype of stress-induced clinical depression, I suspect yes.

RAZ: Amazing. I mean, in theory, we could prevent some types of depression from happening even before they happen.

BRACHMAN: That is my hope. That is, you know, I think the thing that keeps me up in the middle of the night when I'm thinking about the next experiments we can work on is sort of that hope.

RAZ: So a couple of years ago, Rebecca and another colleague at Columbia University were studying the effects of a drug called Calypsol as an antidepressant in mice. And it's still in the very early stages, but what they found could possibly change the way we think about treating depression and PTSD or even preventing them from happening at all. Here's Rebecca Brachman on the TED stage.

(SOUNDBITE OF TED TALK)

BRACHMAN: One of the experiments I was running, we would stress the mice. And we used that as a model of depression. And a normal mouse will explore, it will be social. Check out what's going on. If you stress a mouse in this depression model, they aren't social, they don't explore. They mostly just kind of hide in that back corner behind a cup. Yet, the mice that had gotten that one injection of Calypsol, they were exploring, they were social.

They looked like they'd never been stressed at all, which is impossible. So we did what you do in science when you're not sure and we ran it again. It seemed like these mice were protected against stress or they were inappropriately happy, however you want to call it. And we were really excited. And then we were really skeptical because it was too good to be true.

So we ran it again. And then we ran it again in a PTSD model. And we ran it again in a physiological model where all we did was give stress hormones. And we had our undergrads run it. And then we had our collaborators halfway across the world in France run it. And every time someone ran it, they confirmed the same thing. It seemed like this one injection of Calypsol was somehow protecting against stress for weeks.

And we only published this a year ago, but since then, other labs have also independently confirmed this effect. So we don't know what causes depression. But we do know that stress is the initial trigger in 80 percent of cases. And depression and PTSD are different diseases. But this is something they share in common, right? It is traumatic stress like active combat or natural disasters or community violence or sexual assaults that causes post-traumatic stress disorder.

And not everyone that is exposed to stress develops a mood disorder. And this ability to experience stress and be resilient and bounce back and not develop depression or PTSD is known as stress resilience. And it varies between people. And we have always thought of it as just sort of this passive property, right?

It's the absence of susceptibility factors and risk factors for these disorders. But what if it were active? Maybe we could enhance it, sort of akin to putting on armor. It was this moment of putting together this idea that if resilience is an active mechanism, theoretically, you could enhance it.

And if people with lower levels of resilience are at greater risk for stress-induced depression, then it actually makes perfect logical sense that if you can increase their resilience, you decrease their risk.

RAZ: And in a sense, like, the medication would steel a human to prepare him or her from the effects of the stress they're about to experience.

BRACHMAN: I think steel is probably the wrong term. It would make them more rubbery or pliable, more resilient. So it's not that, you know, stress just has no effect on you. It's that, you know, you could have actually a very strong reaction to the initial stress. But you bounce back. It's, you know, the grass that bows over in the wind and then straightens back up after the wind has passed as opposed to this sort of rigid, you know, a stressor comes and you break.

RAZ: So, I mean, you could imagine if this works that somebody going into combat, say, or somebody about to - a firefighter about to go into a burning building would be able to take this medication and it - and there might be a good chance that it would prevent the effects of that stress or trauma.

BRACHMAN: Very possibly. And I think more important than the compounds that we're looking at now and the research that we're doing now is the idea, this idea that it might be possible to prevent these disorders. So even if it doesn't come, you know, directly from the research we're doing now, the fact that we can now put this idea into the world and other researchers can work on it, I think, jointly, yes, it might be possible.

RAZ: So are you optimistic about where this technology is headed?

BRACHMAN: I am optimistic that it might actually work. You know, the leap from mice and animal studies to humans is this huge sort of canyon. So, you know, there's always the possibility that none of this translates. But the effects we've seen so far in the lab, they're so robust. You know, they're some of the most reproducible effects that I've seen in my time in the field. So I am optimistic based on the science that this is a thing within, you know - it might take 50 years but that it might actually be feasible to prevent some of these disorders.

RAZ: Rebecca Brachman. She's a neuroscientist from Columbia University. You can see her full talk at ted.com. Transcript provided by NPR, Copyright NPR.